<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <title>盒子模型</title>
    <link href="main.css" rel="stylesheet" type="text/css">
</head>

<body>
    <div class="box1">
        <div class="box2">盒子2-1<img src="picon6.png"></div>
        <div class="box2">盒子2-2</div>
        <span class="box2">盒子2-3</span>
    </div>

</body>

</html>